Hi @Hannah_77 - Thanks for bringing this question to the community!

The REI Sub Alpine Tent uses a silicone-based treatment. Hopefully when paired with the information from the other threads on tent seams flaking, you will be set to make progress on fixing those flaking seams.

For the window, we are hopeful others in the community will share what has worked for them. We also want to give the suggestion of using Tenacious Tent Tape to adhere the window back to the tent. Without seeing your specific instance it is impossible to say it will work for sure, but that tape is designed to work well on tents and has a strong adhesive.

Hopefully this helps!

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